Psychrometrics - RH from Dew Point
Relative humidity from dry-bulb and dew-point temperatures using the Tetens saturation-pressure formula.
Relative humidity
69.9%
Vapour pressure (at dew-point)
2.644kPa
Formula, assumptions, and limits
Tetens formula gives P_sat in kPa to within 0.1 % over −20 to +60 °C. Dew point equals dry-bulb when RH = 100 %; they always satisfy T_dp ≤ T_db.
Symbol legend
| Symbol | Meaning | Unit | Source |
|---|---|---|---|
| Dry-bulb temperature | °C | sensor | |
| Dew-point temperature | °C | sensor / chilled-mirror | |
| Relative humidity | % | result |